Renewable fuse plug



N. BOHLIN AND S. FORNER.

RENEWABLE FUSEPLUG.

APPLlcAroN FILED MAR. lo, 192|.

l1429672' PatentedSept. 19, 1922.

Patented Sept. 19, 1922.-.

UNITED srlifljlas" PATENT OFFICE.

RENEWABLE rUsE PLUG. I

Application `led 'March 10, 1921. Serial No. 451,289.

To all wko/m, it may concern Be it known that we, NELs BoHLIN and SVEN FORNER, citizens of the United States, residing at 1640 Farragut Avenue, Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Renewable Fuse Plugs, of which the following is a specification.

The present invention relates to a fuse plug adapted to support a renewable fuse and will be fully understood from the following description of a device in which it is embodied, illustrated by the accompanyino' drawings, in which- 2Figure 1 is a vertical sectional view of a screw plug embodying the invention;

Fig. 2 is a plan View of the plug;

Fig. 3 is a vertical sectional view taken on a right angle to the. section line of Fig. 1, as indicated by the line 3 of Fig. 2'; l

Fig. 4 is applan View of a renewable fuse element suitable for use in the plug;

Fig. 5 is a detailed elevation of certain of the fuse retaining elements, shown separated from the remainder of the plug, and

Fig. 6 is a separated perspective view of the fuse retaining elements.

Referring more particularly to the drawings, the numeral 10 indicates the body of the plug suitably constructed of porcelain or' other insulating material, and provided with a central fuse chamber 11, open at the top and tapering towards the bottom. The body 10 of the fuse is provided with a metal sheet 12V encircling it and adapted to form a screw contact with the threaded interior of a standard socket. A second contact member 13 is formed at the base of the plug by a suitably stamped or spunl metallic member. In the enlarged upper portion of the central chamber 11, two fuse contact members or terminals 14 are provided, these contact members having horizontal contact surfaces 15 resting upon suitable shoulders or ledges 16 formed of the body material of the plug. One of these fuse terminals is connected by a suitable conductor or lead 17 to the Contact member 13 and the other is connected by a lead 18 passing through a suitable bore in the body of the plug to the Contact member 12.

Each of the fuse contact members or terminals 14 has, in addition to the horizontal contact surface 15, an upturned lug 19 stamped o'r otherwise suitably formed on each side of the said contact surfaces. A

disk 2O of libre or other suitable material is hingedly atta'ched'within the upper portion of the chamber 11,A its pivotal axis being \preferably parallel to the line between the 19 of the terminals 14. A double spring member 24 is secured to the tongue 23 of each of the plates 22, a portion of the disk 20 being cut out to permit the passage of the spring extensions.

In using the plug, the hinged disk 2O is raised and-a fuse element 25, preferably as shown 1n Fig. 4, is laid across the plug between the terminals 14. rl`he fuse element is preferably provided with flattened or spadelike ends 26, which rest upon the horizontal contact portion 15 between the upturned lugs 19. The hinged disk is then closed down, whereupon the tongues 23 of the plates 22 attached to the disk are positioned between the lugs 19 on ytop of the ends 26 of the fuse element. The spring members 24 project upwardly and are made to serve as clamps to hold the disk and the fuse rmly in position by screwing down upon the top of the .plug a cap 27, to the interior of which is secured a ring 28 of libre or other suitable insulating material, this ring being so positionedvas to engage the spring elements 24. It is desirable that the cap be provided with a central opening closed with a transparent mica disk 29 and that an opening be likewise provided in the hinged disk 20 to make the condition of the fuse visible.

Although the present invention has been' described in connection with the specific details of an embodiment thereof, it is not intended that these details shall be regarded as limitations upon the scope of the invention, except in so far as included in the accompanying claims.

We claim:

1. A fuse plug having an internal fuse chamber, fuse terminals in said chamber, a plate of insulating material hingedly attached to the body ofthe plug and adapted, when in closed position, to rest upon the fuse terminals and retain a fuse member in po sition thereupon, and means for retaining said plate in closed position.

2. A fuse plug having an internal fuse chamber, fuse terminals in `said chamber, a plate of insulating material hingedly attached to the body of the plug and adapted,y

when in closed position, to rest upon the fuse terminals and retain a fuse member in position thereupon, and a screw cap for said plug adapted to close the fuse chamber and retain the plate in closed position therein.

3. A fuse plug having an internal fuse chamber, fuse terminals in said chamber, a plate of insulating material hingedly attaclied to the body of the plug and adapted, when in closed position, to rest upon the fuse terminals and retain a fuse 'member in position thereupon, spring members mountcap andadapted to engage the spring members on the plate.

.4. A fuse plug having an internal fuse chamber, fuse terminals in the chamber at opposite sides thereof, said fuse elements l being provided With seats to receive the ends ofa fuse member, a fuse member extending between said terminals with its ends resting against said seats, a libre disk hin ed Within said chamber and adapted to c. ose down to engage the fuse member and retain it in position on saidterminals and a screw cap for the fuse plug adapted to close the fuse chamber and retain the disk-in closed position therein.

ed on said plate and a screw cap for said plug adapted to close the fuse chamber and ring of insulating material secured to the NELs BoHLIN. SVEN FORNER. 

